In the labeling machine shown in my U.S. Pat. No. 4,060,229 there is a glue applying roll, a label magazine and picker so arranged that the picker moves along a path to first receive glue from the glue applying roll, then engage a label in the label magazine from which it removes the label and transfers it to a transfer drum whereupon the latter applies the glue coated label to a container. When a gap occurs in the procession of containers or a run of containers has been completed so that there are no containers, it is customary to retract the label magazine to avoid wasting labels. Since no labels are being picked, the glue which would ordinarily have been removed from the pickers is not so removed and builds up in excess on the pickers. Hence, when the labeling operation is resumed, the first few labels will have an excessive amount of glue. Furthermore, because the pickers are rotating at a relatively high speed, the centrifugal force throws the excess glue off onto adjacent parts. To avoid this, it is customary when there is a gap in the procession of containers or no containers to stop the apparatus and wait. When the procession of containers is resumed, the labeling instrumentalities are restarted to allow the glue to build up on the surface of the glue applying roll in the proper amount to stick the labels to the containers. This is a critical operation and an operator must learn how to run the apparatus to make the proper adjustments to provide for the correct thickness of glue, otherwise the labels will not stick. It is the purpose of this invention to avoid the foregoing difficulties and the risk that an operator will not make the proper adjustment by automatically reducing the thickness of glue on the faces of the pickers, that is, to prevent a buildup of glue on them without completely removing the glue therefrom by reducing the thickness of the glue on the surface of the glue applying roll and when the labeling operation is resumed, to restore the required thickness of glue to the labeling instrumentalities.